Griekspoor-Arnaldi: Paris counts for little in Montréal

In May, on the clay of Roland Garros, Matteo Arnaldi beat Tallon Griekspoor in the first round in four sets, 6-7(9), 6-3, 7-6(6), 6-3, and went all the way to the semi-finals from there. Today they meet again in the third round in Montréal, the Italian ranked 35 in the world and seeded 30, the Dutchman slipped to No. 69. Griekspoor is the favourite, and the reason is the surface: on the medium-paced hard court at IGA Stadium his tennis ends the rally before Arnaldi can get into it.

Griekspoor's second serve is the anomaly of the week

Against Lorenzo Sonego in the first round, Griekspoor won 75% of points behind his first serve (33 of 44) and 70% behind his second (19 of 27), closing it out 7-6(5), 7-5 in one hour and fifty minutes. The next day, against Alexander Zverev, world No. 3 and top seed, he climbed to 82% on first serve (45 of 55) and held 60% on second (15 of 25).

It is the second number that is the strange one. A second serve holding above 60% erases the window in which the returner takes the initiative without risk, and forces him to build from the back every single time. Zverev stopped at 40% of points on the Dutchman's second serve and converted a single break point in the entire match: 6-7(3), 6-2, 6-4, with four breaks from nine chances for Griekspoor.

The rest of the match followed the same pattern. Twenty forehand winners, 17 points won out of 18 at the net. Griekspoor played almost everything inside the first shots of the rally, and that is how a player who had won two of his eleven previous meetings with Zverev recorded his eighth career win over a top-10 opponent.

The hard court takes away the phase of play Arnaldi lives in

Arnaldi's 2026 on fast courts is a short, ugly list. A loss to Rublev at the Australian Open (6-4, 6-2, 6-3), 6-0, 6-1 against Mackenzie McDonald at Indian Wells, out to Shevchenko in Miami, a retirement in Washington eleven days ago while trailing Musetti 6-0, 3-1. His win over Fabian Marozsan in the second round here, 7-5, 2-6, 6-4, came after a seeded bye and cost him three sets.

The issue is not form: it is that his tennis asks for time. In Paris he lost the first set on a tie-break, 9-11, and stayed in the match for another three sets, moving Griekspoor from one corner to the other until the Dutchman missed on the tenth ball. On hard courts that tenth ball never comes. If Griekspoor serves the way he served on Tuesday and Wednesday, a large share of the points in which Arnaldi is returning will be over before he can set foot inside the court.

There is a physical question too. The Washington retirement came from a foot problem, and since then Arnaldi has played a single match, the three sets against Marozsan.

The prediction, and what would overturn it

Griekspoor starts as the favourite, the difference from Paris lies entirely in the number of rallies the court allows.

The condition that would overturn it is precise: Griekspoor's first-serve percentage. Against Zverev he was at 69%, above his seasonal average of around 64%. Below 60% the picture changes, because every extra second serve is one more neutral rally, and the neutral baseline rally is Arnaldi's ground.

The second variable is how he holds up at the end of sets. Griekspoor arrives from a year closed at a loss, with his ranking down from No. 25 in February to 69 this week and a retirement from the Dubai final with a left hamstring problem. This week he won a tie-break against Sonego and landed two breaks in the third set against Zverev, then served out the match at 5-4. Those are exactly the situations that have escaped him most often since February. If Arnaldi drags him back there, the prediction gets rewritten on court.